Models 947, 948 and 960 Leak Detectors Operations and Service Manual
3-31
9. Be sure the TEST LED is on, and press the
AUTO CAL
button.
Do not continue if a condition code is displayed. Consult the
NOT READY
Condition
Code Chart Table 3-2 on page 3-29 and follow instructions.
❑
The STD LEAK LED is on; AUTO CAL is also on.
❑
The LEAK RATE display mantissa and exponent values change as a function of auto
tuning.
❑
The STD LEAK LED goes off. The LEAK RATE display changes again and
approximately 20 seconds later, the ZERO LED illuminates to signify the zero
procedure is operating, then it goes off.
❑
The AUTO CAL LED goes off, and the HOLD LED illuminates.
❑
The LEAK RATE display mantissa is zero (one LED bar lit) on the most sensitive
LEAK RATE range exponent.
Calibration is complete when the AUTO CAL LED goes out.
10. Recheck
STD LEAK
reading (Steps 7 and 8).
11. Press either the
START
or
VENT
button to continue operation following the AUTO CAL
routine.
3.14 Operating Procedures
The testing parameters vary from one manufacturing environment to another. Appendix G,
“Leak Detection Theory” describes the conditions under which the 947/948/960 Leak
Detectors can be utilized. There are many applications. A Varian Vacuum Technologies
representative is always available for technical assistance.
Whatever the leak detection situation, testing is accomplished in one of the two operating
procedures:
❑
❑
Requirements:
❑
After shutdown of a leak detector, a complete startup is necessary as outlined in
Start-up Procedure.
❑
Verify the integrity of the leak detector with the Calibration and Sensitivity Checks
Procedure on a daily basis or as necessary.
